Add SyncSocket::ReceiveWithTimeout() and SyncSocket unit tests.

base/sync_socket.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_SYNC_SOCKET_H_
 #define BASE_SYNC_SOCKET_H_
 
 // A socket abstraction used for sending and receiving plain
 // data.  Because the receiving is blocking, they can be used to perform
 // rudimentary cross-process synchronization with low latency.
 
 #include "base/basictypes.h"
 #if defined(OS_WIN)
 #include <windows.h>
 #endif
 #include <sys/types.h>
 
 #include "base/base_export.h"
 #include "base/compiler_specific.h"
 #include "base/synchronization/waitable_event.h"
+#include "base/time/time.h"
 
 namespace base {
 
 class BASE_EXPORT SyncSocket {
  public:
 #if defined(OS_WIN)
   typedef HANDLE Handle;
 #else
   typedef int Handle;
 #endif
@@ skipping 20 matching lines @@
   // length is the length of the data to send (must be non-zero).
   // Returns the number of bytes sent, or 0 upon failure.
   virtual size_t Send(const void* buffer, size_t length);
 
   // Receives a message from an SyncSocket.
   // buffer is a pointer to the buffer to receive data.
   // length is the number of bytes of data to receive (must be non-zero).
   // Returns the number of bytes received, or 0 upon failure.
   virtual size_t Receive(void* buffer, size_t length);
 
+  // Same as Receive() but only blocks for data until |timeout| has elapsed.

[jar (doing other things), 2013/10/14 15:31:07]

nit: "... or |buffer| |length| is exhausted."

[DaleCurtis, 2013/10/14 19:25:13]

Done.

+  // Currently only timeouts less than one second are allowed.  Timeouts will
+  // return the amount of data read prior to timeout.

[jar (doing other things), 2013/10/14 15:31:07]

nit: Remove leading words "Timeout will" and trailing words "prior to timeout." 
It should just be:

Returns the amount of data read.

[DaleCurtis, 2013/10/14 19:25:13]

Done.

+  virtual size_t ReceiveWithTimeout(void* buffer,
+                                    size_t length,
+                                    TimeDelta timeout);
+
   // Returns the number of bytes available. If non-zero, Receive() will not
   // not block when called. NOTE: Some implementations cannot reliably
   // determine the number of bytes available so avoid using the returned
   // size as a promise and simply test against zero.
   size_t Peek();
 
   // Extracts the contained handle.  Used for transferring between
   // processes.
   Handle handle() const { return handle_; }
 
@@ skipping 24 matching lines @@
 
 #if defined(OS_WIN)
   // Since the Linux and Mac implementations actually use a socket, shutting
   // them down from another thread is pretty simple - we can just call
   // shutdown().  However, the Windows implementation relies on named pipes
   // and there isn't a way to cancel a blocking synchronous Read that is
   // supported on <Vista. So, for Windows only, we override these
   // SyncSocket methods in order to support shutting down the 'socket'.
   virtual bool Close() OVERRIDE;
   virtual size_t Receive(void* buffer, size_t length) OVERRIDE;
+  virtual size_t ReceiveWithTimeout(void* buffer,
+                                    size_t length,
+                                    TimeDelta timeout) OVERRIDE;
 #endif
 
   // Send() is overridden to catch cases where the remote end is not responding
   // and we fill the local socket buffer. When the buffer is full, this
   // implementation of Send() will not block indefinitely as
   // SyncSocket::Send will, but instead return 0, as no bytes could be sent.
   // Note that the socket will not be closed in this case.
   virtual size_t Send(const void* buffer, size_t length) OVERRIDE;
 
  private:
 #if defined(OS_WIN)
   WaitableEvent shutdown_event_;
   WaitableEvent file_operation_;
 #endif
   DISALLOW_COPY_AND_ASSIGN(CancelableSyncSocket);
 };
 
 #if defined(OS_WIN) && !defined(COMPONENT_BUILD)
 // TODO(cpu): remove this once chrome is split in two dlls.
 __declspec(selectany)
     const SyncSocket::Handle SyncSocket::kInvalidHandle = INVALID_HANDLE_VALUE;
 #endif
 
 }  // namespace base
 
 #endif  // BASE_SYNC_SOCKET_H_